Sofia Isdatelstvo na Bolgarskata Akademiya na Naukite 1976
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Artikel Jurnal
Hongkong : City University of Hongkong, 2007,
Majalah, Jurnal, Buletin
Rene Suhardono, author
kompas media nusantara , 2019
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Epstein, A.L., author
Australian Univ. Press, 1971
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